Gas delivery system for reducing oxidation in wire bonding operations

Abstract

A wire bonding machine is provided. The wire bonding machine includes a bonding tool and an electrode for forming a free air ball on an end of a wire extending through the bonding tool where the free air ball is formed at a free air ball formation area of the wire bonding machine. The wire bonding machine also includes a bond site area for holding a semiconductor device during a wire bonding operation. The wire bonding machine also includes a gas delivery mechanism configured to provide a cover gas to: (1) the bond site area whereby the cover gas is ejected through at least one aperture of the gas delivery mechanism to the bond site area, and (2) the free air ball formation area.

1. A gas delivery mechanism of a wire bonding machine configured to provide a cover gas in connection with a wire bonding operation, the gas delivery mechanism comprising:
 a body portion defining a through hole extending from a top surface of the body portion to a bottom surface of the body portion, the through hole being tapered along its entire length from the top surface to the bottom surface such that a diameter of the tapered through hole at the bottom surface is larger than a diameter of the tapered through hole at the top surface, the body portion being configured to receive an electrode of a wire bonding machine, the body portion defining an aperture coincident with the through hole configured to receive a tip portion of the electrode; and 
 a gas inlet for providing a cover gas to the body portion, the body portion defining a cavity for receiving the cover gas from the gas inlet, the cavity including a gas outlet at the through hole. 
 
     
     
       2. The gas delivery mechanism of  claim 1  wherein a portion of the cavity adjacent the gas outlet follows a curved path. 
     
     
       3. The gas delivery mechanism of  claim 1  further comprising a second gas inlet, the second gas inlet configured to provide a cover gas to a second cavity defined by the gas delivery mechanism, the second cavity including a second gas outlet at the bottom surface of the body portion. 
     
     
       4. The gas delivery mechanism of  claim 3  wherein a portion of the second cavity directly adjacent the second gas outlet follows an angled path from the second gas outlet into an interior portion of the body portion. 
     
     
       5. The gas delivery mechanism of  claim 1  wherein the body portion is formed of a polyimide material.